If the base is decreased by 50%, it becomes 9. We get this by simply multiply 18 * 0.5
If the height is decreased by 50%, it becomes 4. Again, we just do 8 * 0.5
The area of a parallelogram is base * height.
9 * 4 = 36
X=-28/3 that is your answer
The radius is half the circumference which is 2
the area is pi times radius squared so you do pi times 2 to the 2nd power

and you will get 12.57